Wireless communications operating according to a predetermined protocol have gained worldwide popularity. The features of the wireless medium include the capacity to address broad geographic areas without expensive infrastructure development such as running cables. The broadband wireless access industry may be based on, for example, Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards.
A wireless communication system may include one or more base stations (BSs), and one or more subscriber stations (SSs). A base station may be any type of communication device configured to transmit data to, and/or receive data from, one or more subscriber stations in the wireless communication system. In some applications, a base station may be referred to as, for example, a Node-B, a base transceiver system (BTS), an access point, a home Node-B, a femto-cell base station, etc. In other applications, a base station may be referred to as a relay station, an intermediate node, or an intermediary. A base station may have a broadcast/reception range within which the base station may wirelessly communicate with one or more subscriber stations. The broadcast/reception range may vary due to power levels, locations, interferences, etc.
A subscriber station may be any type of communication device configured to wirelessly transmit data to, and/or receive data from, a base station in the wireless communication system. A subscriber station may be, for example, a server, a client, a desktop computer, a laptop computer, a network computer, a workstation, a personal digital assistant (PDA), a tablet personal computer (PC), a scanner, a telephony device, a pager, a camera, a television, a hand-held video game device, a musical device, etc. In addition, a subscriber station may include one or more wireless sensors in a wireless sensor network configured to perform centralized and/or distributed communication. In some applications, a subscriber station may be a mobile computing device. In other applications, a subscriber station may be a fixed computing device operating in a mobile environment, such as a bus, a train, an airplane, a boat, a car, etc.
The IEEE 802.16 family of standards support a multicast and/or broadcast service (MBS), also known as a multimedia broadcast multicast service (MBMS), which can provide content data to a plurality of users who desire to receive the same service in a communication network. For example, the content data may be movies, games, files, software programs, or TV programs, and is usually provided by one or more content providers. A subscriber station may subscribe to an MBS. As a result, the subscriber station may receive MBS data that includes MBS control information and content data, through access to one or more base stations in the communication network. In addition to the IEEE 802.16 family of standards, standards promulgated by 3rd Generation Partnership Project (3GPP), which is a collaboration of certain standards development organizations, may also support MBSs. The 3GPP standards may include the Universal Mobile Telecommunication System (UMTS) standard, the High-Speed Uplink Packet Access (HSUPA) standard, the Evolved High-Speed Packet Access (HSPA Evolution) standard, the Long Term Evolution (LTE) standard, the LTE Advanced standard, etc.
Typically, MBSs may be provided based on single-cell transmission or multi-cell transmission. FIG. 1 illustrates a schematic block diagram of a conventional communication system 100 for providing MBSs based on a single-cell transmission mode, also known as a single-BS access mode. The communication system 100 may include a plurality of base stations each serving a cell. For convenience of illustration, first and second base stations 102 and 104 are shown in FIG. 1. The base stations 102 and 104 serve first and second cells 106 and 108, respectively.
Based on the single-cell transmission mode, base stations provide MBSs independently, and a subscriber station in a cell only receives signals including MBS data from a base station serving that cell. For example, a subscriber station 110 in the cell 106 only receives signals from the base station 102 to receive an MBS. Also for example, a subscriber station 112 in the cell 108 only receives signals from the base station 104 to receive an MBS.
FIG. 2 illustrates a schematic block diagram of a conventional communication system 200 for providing MBSs based on a multi-cell transmission mode, also known as a multi-BS access mode. The communication system 200 may include a plurality of base stations each serving a cell. For convenience of illustration, first and second base stations 202 and 204 are shown in FIG. 2. The base stations 202 and 204 serve first and second cells 206 and 208, respectively. The cells 206 and 208 may have an overlapped area covered by both the base stations 202 and 204.
Based on the multi-cell transmission mode, base stations, e.g., the base stations 202 and 204, participating in multi-cell transmission may be coordinated in advance and transmit multicast signals at substantially the same time. In such situation, a subscriber station, e.g., a subscriber station 210, 212, or 214, may receive signals including the same MBS data from the base stations 202 and 204. This may improve reliability of the received signals.
In addition, a base station may provide one or more MBSs in parallel. Moreover, some of the MBSs may be provided based on single-cell transmission, and other ones of the MBSs may be provided based on multi-cell transmission.